In every case, the men and women were courteous and professional--which I cannot say, from direct experience, about other groups (IT customer "support," for instance).

The IRS just has to cope with incomprehensible law, courtesy of the Fools on the Hill. Tech support has to deal with endless calls, half of which can be resolved by asking "Is it plugged in?" and "Is it turned on?" I have to admit to snapping a couple of times when I did tech support.